Show Variables: Where is the Time Spent?

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1

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This topic has been translated from a Chinese forum by GPT and might contain errors.

Original topic: show varialbes 时间消耗在哪了

| username: h5n1

v7.5.1
Executed 21 times in half an hour, averaging 11 seconds

e7126a76128abe21e7ca26c63a2f8f7
e7126a76128abe21e7ca26c63a2f8f71257×111 10.4 KB

e713a2687074c531e9d531f0af18480
e713a2687074c531e9d531f0af18480914×666 76.7 KB

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81a831fe6e940d3c533f1a62189d3681380×302 24.3 KB

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57b21c79aa82e8e4449ee81cd618364993×810 29.9 KB

Manual speed test is very fast

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image576×706 13.7 KB

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| username: TiDBer_QYr0vohO | Original post link

It feels like it might be network overhead.

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| username: xiaoqiao | Original post link

How about trying union all?

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| username: 舞动梦灵 | Original post link

Where did this SQL come from?? Was it executed by the system backend? I didn’t see anything like this in the slow SQL logs.

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| username: yiduoyunQ | Original post link

Look in the slow query.